The DOI matches its Crossref record; 36 of the 36 references it cites were found in a registry or an index.
Time to pregnancy: results of the German prospective study and impact on the management of infertility
Abstract
BACKGROUND: The likelihood of spontaneous conception in subsequent cycles is important for a balanced management of infertility. Previous studies on time to pregnancy are mostly retrospective and biased because of exclusion of truly infertile couples. The study aim was to present a non-parametric estimation of cumulative probabilities of conception (CPC) in natural family planning (NFP) users illustrating an ideal of human fertility potential. METHODS: A total of 346 women was observed who used NFP methods to conceive from their first cycle onwards. The couples practising NFP make optimal use of their fertility potential by timed intercourse. The CPC were estimated for the total group and for couples who finally conceived by calculating Kaplan-Meier survival rates. RESULTS: A total of 310 pregnancies occurred among the 346 women; the remaining 36 women (10.4%) did not conceive. Estimated CPC for the total group (n = 340 women) at one, three, six and 12 cycle(s) were 38, 68, 81 and 92% respectively. For those who finally conceived (truly fertile couples, n = 304 women), the respective pregnancy rates were 42, 75, 88 and 98% respectively. Although the numbers of couples in both groups were similar, the impact of age on time to conception, as judged by the Wilcoxon test, was less in the truly fertile than in the total group. CONCLUSIONS: Most couples conceive within six cycles with timed intercourse. Thereafter, every second couple is probably either subfertile or infertile. CPC decline with age because heterogeneity in fecundity increases. In the subgroup of truly fertile couples, an age-dependent decline in CPC is statistically less obvious because of high homogeneity, even with advancing age.
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Cites
Incidence of early loss of pregnancy
Wilcox, A. J., Weinberg, C. R., O'Connor, J. F., Baird, D. D., Schlatterer, J. P., Canfield, R. E., Armstrong, E. G., & Nisula, B. C. (1988) · New England Journal of Medicine · doi:10.1056/nejm198807283190401 · Cited by 2,354
The variability of female reproductive ageing
te Velde, E. R. (2002) · Human Reproduction Update · doi:10.1093/humupd/8.2.141 · Cited by 1,214
Bonde, J. P. E., Ernst, E., Jensen, T. K., Hjollund, N. H. I., Kolstad, H., Scheike, T., Giwercman, A., Skakkebæk, N. E., Henriksen, T. B., & Olsen, J. (1998) · The Lancet · doi:10.1016/s0140-6736(97)10514-1 · Cited by 791
Estimates of human fertility and pregnancy loss
Zinaman, M. J., Clegg, E. D., Brown, C. C., O’Connor, J., & Selevan, S. G. (1996) · Fertility and Sterility · doi:10.1016/s0015-0282(16)58144-8 · Cited by 604
Changes with age in the level and duration of fertility in the menstrual cycle
Dunson, D. B. (2002) · Human Reproduction · doi:10.1093/humrep/17.5.1399 · Cited by 574
PROGNOSTIC ASSESSMENT OF FEMALE FECUNDITY
Navot, D., Rosenwaks, Z., & Margalioth, E. (1987) · The Lancet · doi:10.1016/s0140-6736(87)92439-1 · Cited by 391
Scheffer, G. J., Broekmans, F. J. M., Dorland, M., Habbema, J. D. F., Looman, C. W. N., & te Velde, E. R. (1999) · Fertility and Sterility · doi:10.1016/s0015-0282(99)00396-9 · Cited by 390
The prognosis for live birth among untreated infertile couples
Collins, J. A., Burrows, E. A., & Willan, A. R. (1995) · Fertility and Sterility · doi:10.1016/s0015-0282(16)57650-x · Cited by 365
Snick, H. K., Snick, T. S., Evers, J. L., & Collins, J. A. (1997) · Human Reproduction · doi:10.1093/humrep/12.7.1582 · Cited by 340
Day 3 serum inhibin-B is predictive of assisted reproductive technologies outcome
Seifer, D. B., Lambert-Messerlian, G., Hogan, J. W., Gárdiner, A. C., Blazar, A. S., & Berk, C. A. (1997) · Fertility and Sterility · doi:10.1016/s0015-0282(97)81865-1 · Cited by 325
Cited by
Ross, D. S., Burch, H. B., Cooper, D. S., Greenlee, M. C., Laurberg, P., Maia, A. L., Rivkees, S. A., Samuels, M., Sosa, J. A., Stan, M. N., et al. (2016) · Thyroid® · doi:10.1089/thy.2016.0229 · Cited by 2,938
“In a German prospective study of 340 such women, 68% became pregnant within 3 months (474).”
BackgroundThyroid Function and Human Reproductive Health
Krassas, G. E., Poppe, K., & Glinoer, D. (2010) · Endocrine Reviews · doi:10.1210/er.2009-0041 · Cited by 1,223
Stephenson, J., Heslehurst, N., Hall, J., Schoenaker, D. A. J. M., Hutchinson, J., Cade, J. E., Poston, L., Barrett, G., Crozier, S. R., Barker, M., et al. (2018) · The Lancet · doi:10.1016/s0140-6736(18)30311-8 · Cited by 1,222
Infertility and the provision of infertility medical services in developing countries
Ombelet, W., Cooke, I., Dyer, S., Serour, G., & Devroey, P. (2008) · Human Reproduction Update · doi:10.1093/humupd/dmn042 · Cited by 720
Demographic and medical consequences of the postponement of parenthood
Schmidt, L., Sobotka, T., Bentzen, J. G., Nyboe Andersen, A., & on behalf of the ESHRE Reproduction and Society Task Force (2012) · Human Reproduction Update · doi:10.1093/humupd/dmr040 · Cited by 656
Metadata
- Authors
- Gnoth, C.
- Venue
- Human Reproduction
- Publisher
- Oxford University Press (OUP)
- Published
- 2003-09-01
- Volume
- 18
- Issue
- 9
- Pages
- 1959-1966
- ISSN
- 0268-1161 (ISSN-L)
- 1460-2350
- OpenAlex
- W2065067996
- Cited by
- 458
- References
- 36
- FWCI
- 11.99
- Type
- journal article
- Language
- en
- Open access
- closed
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