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Infertility in Females

Infertility in Females

Female infertility is defined as the inability to conceive after a year of regular, unprotected intercourse and affects about 10–15% of couples worldwide. The primary cause of female infertility is ovulatory disorders, which hinder the release of eggs. These disorders can be classified as hypothalamic amenorrhea, polycystic ovarian syndrome (PCOS), premature ovarian failure, and hyperprolactinemic anovulation disorders.
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Infertility in Males

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Related Experiment Video

Updated: Jul 3, 2026

Collection of Human Follicular Fluid, Follicle Somatic Cells, and Immature Oocytes from Individuals Undergoing In Vitro Fertilization

Collection of Human Follicular Fluid, Follicle Somatic Cells, and Immature Oocytes from Individuals Undergoing In Vitro Fertilization

Published on: October 24, 2025

Fertility transitions in developing countries: progress or stagnation?

John Bongaarts¹

¹Population Council, One Dag Hammarskjold Plaza, New York, NY 10017, USA. jbongaarts@popcouncil.org

Studies in Family Planning

|August 6, 2008

Summary

This summary is machine-generated.

Fertility decline is slowing in many developing nations. Over half of sub-Saharan African countries studied show stalled fertility transitions, indicating a potential shift in demographic trends.

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Determination of Reproductive Competence by Confirming Pubertal Onset and Performing a Fertility Assay in Mice and Rats

Determination of Reproductive Competence by Confirming Pubertal Onset and Performing a Fertility Assay in Mice and Rats

Published on: October 13, 2018

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Last Updated: Jul 3, 2026

Collection of Human Follicular Fluid, Follicle Somatic Cells, and Immature Oocytes from Individuals Undergoing In Vitro Fertilization

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Published on: October 24, 2025

Determination of Reproductive Competence by Confirming Pubertal Onset and Performing a Fertility Assay in Mice and Rats

Determination of Reproductive Competence by Confirming Pubertal Onset and Performing a Fertility Assay in Mice and Rats

Published on: October 13, 2018

Area of Science:

Demography
Global Health
Population Studies

Background:

Global fertility rates have seen a rapid decline over the last 25 years, particularly in developing countries.
Demographic projections often assume a continuous downward trend in fertility until replacement levels are reached.
Emerging evidence indicates a potential deceleration or stalling of fertility declines in several countries undergoing demographic transition.

Purpose of the Study:

To investigate the pace of fertility change in developing countries with available Demographic and Health Surveys.
To determine if ongoing fertility transitions are decelerating or stalling in these nations.

Main Methods:

Analysis of fertility trends using data from multiple Demographic and Health Surveys (DHS) in developing countries.
Comparative analysis of the pace of fertility decline across different time periods, focusing on the mid-1990s and around 2000.

Main Results:

The average pace of fertility decline in sub-Saharan African countries was slower around 2000 compared to the mid-1990s.
More than 50% of the countries in the sub-Saharan African region experiencing fertility transition have shown stalled fertility rates.

Conclusions:

Fertility transitions in sub-Saharan Africa may be decelerating or stalling, contrary to typical projection assumptions.
The findings highlight the need to re-evaluate demographic projections and understand the factors contributing to stalled fertility declines.