Asian Journal of Research in Nursing and Health

Background: Sex ratio is important for human life since its creation, some families prefer male than females, also its related to some medical problems that affect certain sex than another. Studies showed that   males are more fragile, and might die earlier than females. Climate has a certain effect on  male to female ratio of the pregnancy outcome and certain  seasons  are in favor of male than female reproduction.

Objectives:  To evaluate the effect of climate and seasonal variation on the sex of live births in a sample of pregnant Iraqi women.

Subjects and Methods: This  study was carried out   on 2424 live babies (apart from 225 miscarriages) of  women attending Al–Numan teaching hospital and Al-Husaynia health care center, from  January 2017 till January 2019.The time of last menstrual period recall was taken from each mother of this study. an early ultrasound test was done to confirm the accuracy of pregnancy duration. The gender of live babies, maternal age and parity were recorded.

Results: The highest birth rate were in Autumn (721) then Winter (662), Spring (577) and the least in summer  (521).

The male to female ratio increased with maternal age. Mothers of  30 years and over have 1.09male female ratio as compared with those under the age of  30 years (0.929).

The male female ratio was highest in Autumn 1.06 compared with other seasons; 0.97, 0.9233, 0.887  Winter, Spring and Summer respectively. The abortion rate was only (0.09) from total births.

Conclusion: The best season for conception in Iraq was Autumn. The total male female ratio regardless the season was 0.9659. The male female ratio was best in Autumn then Winter, Spring, lastly Summer. Sex differences shows that;  males  are conceived in seasons of more favorable conditions for reproduction.