The last decade has transformed the physician's approach to infertility. The development of IVF for its treatment has so improved our capacity to overcome this most distressing of disabilities that we now need to revise many of our working ideas on how it can come about. This is not because new causes have been discovered. Rather, an appreciation has been gained of how apparently minor disturbances can combine to cause a major disruption in the expectation of pregnancy. At the best of times-and sometimes, no doubt, at the worst of times getting pregnant is a matter of chance. The parameter that describes this chance is the monthly probability of conception, known among epidemiologists as fecundability (f) (probability of achieving pregnancy in one menstrual cycle), and is similar to "monthly fecundity" (monthly probability of a live birth in one cycle exposed to the risk of pregnancy) (1). Like every statistic in biology, fecundability has a wide distribution of values in the population (modeled in Fig. 1). Figure 1 also illustrates a group of couples with a fecundability value of zero-meaning complete infertility, or sterility, which affects perhaps 5% of couples attempting to achieve a pregnancy.
fecundability monthly probability conception infertility, Jansen fecundability assisted conception perspective, monthly fecundity rate population distribution infertility, IVF impact understanding infertility causes, minor fertility disturbances combined effect pregnancy, sterility prevalence couples attempting pregnancy, fecundability distribution population model subfertility, cumulative conception probability infertile couples, assisted reproductive technology changing infertility paradigm, epidemiology fecundability subfertility causes review
PMID 7615098 7615098 DOI 10.1016/s0015-0282(16)57718-8 10.1016/s0015-0282(16)57718-8
Cite this article
Jansen, R. P. (1995). Elusive fertility: fecundability and assisted conception in perspective. Fertility and sterility, 64(2), 252-254. https://doi.org/10.1016/s0015-0282(16)57718-8
Jansen RP. Elusive fertility: fecundability and assisted conception in perspective. Fertil Steril. 1995;64(2):252-254. doi:10.1016/s0015-0282(16)57718-8
Jansen, Robert P.S. "Elusive fertility: fecundability and assisted conception in perspective." Fertility and sterility, vol. 64, no. 2, 1995, pp. 252-254.
Keywords
Female, Fertility, Fertilization in Vitro, Humans, Infertility/therapy, Pregnancy
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# Ethnic diversity in fertility treatment 2018
UK ethnicity March 2021
[**Download the underlying dataset as .xlsx (27kb)**](https://www.hfea.gov.uk/media/3348/2021-03-03-bame-report-suppl_mental-underlying-data-final.xlsx "download the underlying data as .xlsx").
## - [Main points](https://www.hfea.gov.uk/about-us/publications/research-and-data/ethnic-diversity-in-fertility-treatment-2018/#mainpoints)
- [Introduction](https://www.hfea.gov.uk/about-us/publications/research-and-data/ethnic-diversity-in-fertility-treatment-2018/#introduction)
- [Section 1. IVF birth rates lowest for patients of Black ethnicities](https://www.hfea.gov.uk/about-us/publications/research-and-data/ethnic-diversity-in-fertility-treatment-2018/#Section1)
- [Section 2. Multiple birth rate higher on average for Black patients](https://www.hfea.gov.uk/about-us/publications/research-and-data/ethnic-diversity-in-fertility-treatment-2018/#Section2)
- [Section 3. White egg donors most commonly used across all ethnic groups](https://www.hfea.gov.uk/about-us/publications/research-and-data/ethnic-diversity-in-fertility-treatment-2018/#Section3)
- [Section 4. Fewer Asian egg and sperm donors compared to UK Asian population](https://www.hfea.gov.uk/about-us/publications/research-and-data/ethnic-diversity-in-fertility-treatment-2018/#Section4)
- [Section 5. Asian patients represent a larger proportion of IVF users](https://www.hfea.gov.uk/about-us/publications/research-and-data/ethnic-diversity-in-fertility-treatment-2018/#Section5)
- [Section 6. Variation in NHS-funded IVF cycles between cycles in larger in younger age groups](https://www.hfea.gov.uk/about-us/publications/research-and-data/ethnic-diversity-in-fertility-treatment-2018/#Section6)
- [Section 7. Black patients start IVF later than other ethnic groups](https://www.hfea.gov.uk/about-us/publications/research-and-data/ethnic-diversit...
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