Definition and research guide
This page combines a MeSH definition, publication statistics and selected research abstracts. It is a starting point for reading the literature, not a medical textbook or a systematic evidence review.
Content available: 4 complete abstracts (729 words), 10 references. Full article text is not stored or reproduced here; follow the PMID, DOI or PMC links to read the original sources and their access terms.
Definition
The sexual union of a male and a female, a term used for human only.
Definition: NLM Medical Subject Headings (MeSH) scope note (Public domain (U.S. National Library of Medicine); attribution requested). View the MeSH record.
Also known as: Sexual Intercourse; Intercourse, Sexual; Sexual Intercourses; Coital Frequency; Coital Frequencies; Frequency, Coital; First Intercourse; First Intercourses.
Where it fits in the MeSH classification
- Broader topics
- Sexual Behavior; Reproduction
- Narrower topics
- Coitus Interruptus
Research landscape
PubMed indexes 8,093 records tagged with the MeSH heading “Coitus” (counts retrieved 2026-10-31). 557 of them (6.9%) were published from 2020 onward, and the busiest period so far is through 1999 with 3,685 records.
Reviews account for 695 records (8.6%) and meta-analyses for 74. Randomized controlled trials number 340 (4.2%) as a share of all records on the topic.
Show the data
| Period | Records |
|---|---|
| through 1999 | 3,685 |
| 2000-2009 | 1,916 |
| 2010-2019 | 1,935 |
| 2020 onward | 557 |
Publication-type chart data
| Type | Records | Share |
|---|---|---|
| Reviews | 695 | 8.6% |
| Meta-analyses | 74 | 0.9% |
| Randomized controlled trials | 340 | 4.2% |
Method: PubMed query "Coitus"[MeSH Terms] with publication-type and date filters, retrieved 2026-10-31.
Reading the evidence in anatomy and physiology
Anatomy describes how body structures are built and physiology describes how they normally work, so most findings here are descriptive or mechanistic rather than evidence about treatment. Much of what is known comes from dissection, imaging, tissue studies and experiments in animals, and measurements in healthy volunteers can differ from those in people with disease or at different ages. Normal ranges vary between individuals and populations. Check whether a result was measured in people or in another species, the age and health of the participants, and the method used.
Evidence from open-access studies
These open-access studies come from PubMed’s best-match results for this heading (papers whose main topic it is), ranked here by citation count, with one recent addition. Each abstract is reproduced in full under its recorded open licence so that you can read the authors’ own words. They illustrate the literature; they are not a systematic summary of it. Citation counts measure attention, not reliability or clinical benefit.
| Study / authors | Year | Source label / design | Europe PMC citations | Licence / source |
|---|---|---|---|---|
| Early sexual debut: prevalence and risk factors among secondary school students in Ido-ekiti, Ekiti state, South-West Nigeria | 2017 | Research article Design not recorded in structured metadata | 70 | cc by PMID 29085388 · DOI · PMC5656187 |
| Factors associated with early resumption of sexual intercourse among postnatal women in Uganda | 2015 | Research article Design not recorded in structured metadata | 42 | cc by PMID 26585992 · DOI · PMC4653924 |
| Early sexual debut and risky sex in young adults: the role of low self-control | 2019 | Research article Design not recorded in structured metadata | 42 | cc by PMID 31703650 · DOI · PMC6839049 |
| Microbial and seminal traces of sexual intercourse and forensic implications | 2025 | Research article Design not recorded in structured metadata | 4 | cc by PMID 41267120 · DOI · PMC12632010 |
Early sexual debut: prevalence and risk factors among secondary school students in Ido-ekiti, Ekiti state, South-West Nigeria [1]
Abstract reading summary — source excerpts
- Opening excerpt
- BackgroundEarly adolescent sexual activity remains a recurring problem with negative psychosocial and health outcomes.
- Closing excerpt
- This will help to reduce the devastating negative psycho-social and health sequels.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (170 words)
BackgroundEarly adolescent sexual activity remains a recurring problem with negative psychosocial and health outcomes. The age at sexual debut varies from place to place and among different individuals and is associated with varying factors. The aim was to determine the prevalence and risk factors of early sexual debut among secondary school students in Ido-Ekiti, South-West Nigeria.MethodologyThis was a cross-sectional study. The respondents were selected using multi-stage sampling technique. Pre-tested, semi-structured, self-administered questionnaire was used to collect data. Data was analyzed using SPSS version 15.ResultsMore than two-thirds, 40(67.8%), had early sexual debut. The prevalence of early sexual debut was about 11%. The mean age of sexual debut was 13.10±2.82; the mean age for early sexual debutants was 11.68±1.98. The mean number of sexual partners was 2.44±1.99. Male gender, having friends who engaged in sexual activities had association with early sexual exposure (pConclusionThe high prevalence of early sexual exposure among the students calls for urgent interventions to stem the trend. This will help to reduce the devastating negative psycho-social and health sequels.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 29085388 · DOI · PMC5656187
Factors associated with early resumption of sexual intercourse among postnatal women in Uganda [2]
Abstract reading summary — source excerpts
- Opening excerpt
- BackgroundDespite being a key component to be addressed during postnatal period, sexuality has long been a subject of secrecy and taboo in Africa.
- Closing excerpt
- Women with high income, low parity, who ever-used contraception or had a spouse with high education level were more likely to have early resumption of sexual intercourse.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (252 words)
BackgroundDespite being a key component to be addressed during postnatal period, sexuality has long been a subject of secrecy and taboo in Africa. Resumption of sexual intercourse after giving birth has been shown to reduce extramarital affairs and consequently reduce risk of sexually transmitted infections like HIV/AIDS. Consequences of early resumption of sexual intercourse include unwanted pregnancy, genital trauma and puerperal infection. The objective of the study was to assess prevalence and factors associated with early resumption of sexual intercourse among postnatal mothers attending postnatal clinic at a National referral Hospital in Uganda.MethodologyA cross-sectional study that employed an interviewer-administered questionnaire was conducted among 374 women who delivered six months prior to conducting the study. The independent variables included socio-demographic characteristics of the participant, socio-demographic characteristics of the spouse, perceived cultural norms, medical history, mode of delivery, and postpartum complications. The dependent variable was timing of resumption of sexual intercourse after childbirth (before or after six weeks postpartum). Data were analysed using SPSS version 16.0.ResultsThe study showed that 105 participants (21.6%) had resumed sexual intercourse before 6 weeks after childbirth. The participants' education level, occupation, and parity; education level of the spouse, age of baby and use of family planning were the factors associated with early resumption of sexual intercourse after child birth (before six weeks postpartum) (p ConclusionMany women resumed sexual intercourse after six weeks. Women with high income, low parity, who ever-used contraception or had a spouse with high education level were more likely to have early resumption of sexual intercourse.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 26585992 · DOI · PMC4653924
Early sexual debut and risky sex in young adults: the role of low self-control [3]
Abstract reading summary — source excerpts
- Opening excerpt
- BackgroundThe purpose of this study was to examine the role of low self-control as a mediator or moderator between early age at sexual debut and risky sexual behavior in young adulthood.
- Closing excerpt
- ResultsApproximately 17% of respondents were ConclusionsThis study confirms the role of executive functions in sexual behaviors and suggests that interventions aimed at improving self-control may be beneficial in reducing risky sexual behavior.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (103 words)
BackgroundThe purpose of this study was to examine the role of low self-control as a mediator or moderator between early age at sexual debut and risky sexual behavior in young adulthood.MethodsData on 5734 male and female Add Health participants were used. Self-control (waves 1 & 3), age at sexual debut (wave 3) and risky sexual behavior (wave 4) were used in a structural equation modeling framework to assess the relationships of interest.ResultsApproximately 17% of respondents were ConclusionsThis study confirms the role of executive functions in sexual behaviors and suggests that interventions aimed at improving self-control may be beneficial in reducing risky sexual behavior.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 31703650 · DOI · PMC6839049
Microbial and seminal traces of sexual intercourse and forensic implications [4]
Abstract reading summary — source excerpts
- Opening excerpt
- BackgroundThe increasing numbers of sexual violence and unresolved rape cases require alternative approaches with higher evidential value to complement existing forensic tools.
- Closing excerpt
- Video Abstract.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (204 words)
BackgroundThe increasing numbers of sexual violence and unresolved rape cases require alternative approaches with higher evidential value to complement existing forensic tools. Predicting recent intercourse is crucial in forensic casework on sexual assaults. In this work, we assessed whether sexual intercourse can be predicted based on the vaginal microbiome and compared it to the gold standard method of semen detection.ResultsUsing a prediction model based on microbiome of 3043 women, intercourse was predicted with 71% accuracy in a balanced cross-validation machine learning setting. This prediction model was validated in a longitudinal intervention study and tested on forensic sexual assault cases. The developed predictor could accurately establish intercourse in 82% of the studied cases. Yet, underwear was found to hold an even greater evidential value and replace the more invasive vaginal sampling for semen detection in some cases with an accuracy of 95%. This was substantiated through a retrospective analysis of 207 forensic sexual assault cases.ConclusionsTaken together, this study revealed that the vaginal microbiome is better at predicting recent sexual intercourse, while the victim's underwear has a clear value as additional biological trace evidence for semen detection. These findings are particularly useful in cases with delayed reporting and are obtained with less invasive sampling. Video Abstract.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 41267120 · DOI · PMC12632010
Key reviews and meta-analyses
The most cited review-type papers among PubMed’s best-match results for this heading, listed with bibliographic details only. Follow the links for the full text and access terms.
- Research article Sexual behaviour in context: a global perspective [5]
- Research article Changing paradigms from a historical DSM-III and DSM-IV view toward an evidence-based definition of premature ejaculation. Part II--proposals for DSM-V and ICD-11 [6]
- Research article Association of episodic physical and sexual activity with triggering of acute cardiac events: systematic review and meta-analysis [7]
- Research article Sexual transmission of Zika virus and other flaviviruses: A living systematic review [8]
- Research article The impact of rheumatic diseases on sexual function [9]
- Research article Timing intercourse to achieve pregnancy: current evidence [10]
References
- Durowade KA, Babatunde OA, Omokanye LO, Elegbede OE, Ayodele LM, Adewoye KR, et al.. Early sexual debut: prevalence and risk factors among secondary school students in Ido-ekiti, Ekiti state, South-West Nigeria. . 2017. PMID 29085388 · DOI · PMC5656187
- Alum AC, Kizza IB, Osingada CP, Katende G, Kaye DK. Factors associated with early resumption of sexual intercourse among postnatal women in Uganda. . 2015. PMID 26585992 · DOI · PMC4653924
- Magnusson BM, Crandall A, Evans K. Early sexual debut and risky sex in young adults: the role of low self-control. . 2019. PMID 31703650 · DOI · PMC6839049
- Ahannach S, Gehrmann T, Spacova I, Wittouck S, Hiers J, Bron PA, et al.. Microbial and seminal traces of sexual intercourse and forensic implications. . 2025. PMID 41267120 · DOI · PMC12632010
- Wellings K, Collumbien M, Slaymaker E, Singh S, Hodges Z, Patel D, et al.. Sexual behaviour in context: a global perspective. Lancet. 2006. PMID 17098090 · DOI
- Waldinger MD, Schweitzer DH. Changing paradigms from a historical DSM-III and DSM-IV view toward an evidence-based definition of premature ejaculation. Part II--proposals for DSM-V and ICD-11. J Sex Med. 2006. PMID 16839326 · DOI
- Dahabreh IJ, Paulus JK. Association of episodic physical and sexual activity with triggering of acute cardiac events: systematic review and meta-analysis. JAMA. 2011. PMID 21427375 · DOI · PMC5479331
- Counotte MJ, Kim CR, Wang J, Bernstein K, Deal CD, Broutet NJN, et al.. Sexual transmission of Zika virus and other flaviviruses: A living systematic review. PLoS Med. 2018. PMID 30040845 · DOI · PMC6057622
- Tristano AG. The impact of rheumatic diseases on sexual function. Rheumatol Int. 2009. PMID 19152092 · DOI
- Stanford JB, White GL, Hatasaka H. Timing intercourse to achieve pregnancy: current evidence. Obstet Gynecol. 2002. PMID 12468181 · DOI
About this article
- Sources
- NLM Medical Subject Headings (definition, synonyms); NCBI PubMed (counts, identifiers); Europe PMC (open-access abstracts and citation counts).
- Verification
- Every reference was resolved against PubMed on 2026-10-31; title, year and DOI matched.
- Review state
- automated source verified; no human expert review has been recorded yet.
- Version
- 1, last updated 2026-10-31.
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Evidence strength
EvidenceHelix's computed view of the study designs behind this topic: how common meta-analyses, randomized trials and reviews are, how recent the literature is, and a plain-language reading. It describes the design mix of the literature. It is not a quality appraisal of any study, and it is not medical advice.