A couple’s fertility window
While a man normally produces sperm all the time, a woman usually releases an egg from one of her ovaries only once during her menstrual cycle. Since the egg can survive up to one day, and a man’s sperm can survive up to five days in a woman’s genital tract after sexual intercourse (under maximal conditions), a couple can be considered fertile for only about five to six days per menstrual cycle.
Modern natural methods
It is important to note here that the Calendar or Rhythm Method is no longer regarded as reliable, especially when used to avoid pregnancy. This method works on the assumption that a woman will have a regular 28-day menstrual cycle where ovulation takes place on day 14 all the time.
Unfortunately this takes place only 13.5 percent of the time. Modern natural methods of family planning, as we shall look at later, are based on easily recognised markers of fertility. Hence they can be used for both regular and irregular cycles, where the users are trained to look for changes in these markers which are highly predictive of the period of ovulation.
Modern natural methods are usually based on the recognition of cervical secretions that the woman discharges. It is important for a couple to seek instruction from a local certified instructor for any of these methods if they decide to use it to try for a baby.
Billings Ovulation Method (BOM)
The BOM was first developed in Melbourne in 1953 by Drs John and Evelyn Billings. Its use has spread to many countries since then, as it has not only been easy to use, but also effective for couples using it to postpone or achieve pregnancy. In a large scale trial in China published in 2003, 14,524 out of 45,280 (32.1 percent) previously infertile couples were able to achieve pregnancy using the BOM.
Naprotechnology (NPT) and fertility care
NPT can be used to help couples with infertility, recurrent miscarriages, irregular cycles, premenstrual syndrome, or abnormal menstrual bleeding. NPT had its beginnings in Omaha, USA, having been developed by Dr Thomas Hilgers since 1978. Based on the changing cervical secretions in a woman’s menstrual cycle as well as her bleeding patterns, a couple will be able to do a form of charting based on the Creighton Model Fertility Care System. This chart is analysed by a medical consultant trained in NPT.
If infertility is the issue, then based on the pattern seen, the NPT trained physician will recommend some tests for the couple to do, to find out the underlying cause of the infertility. These tests may take the form of blood tests, sperm count or ultrasound, or any other gynaecological investigation as deemed necessary. Through these investigations, various problems can be detected, such as hormonal abnormality, cervical mucus dysfunction, problems with egg development, endometriosis and so on.
Once these and other problems are identified and treated, NPT enables the couples to conceive using natural acts of intercourse.
Hormonal assessment is continued throughout the pregnancy and support provided if needed.
A recent study in Ireland found that overall, 52.8 percent of patients completing treatment could expect to have a successful live birth, most often a single healthy baby.
While there are other natural methods of helping couples conceive, such as the Symptothermal and the BBT (Basal Body Temperature) methods, the most widely used and researched modern methods remain the BOM and NPT, both of which are available in Singapore. They provide useful alternatives to couples who have problems with infertility and want to use natural methods to overcome their problems, including Catholic couples who wish to remain faithful to the Church’s teachings in this area of human procreation.
By Dr John Hui
Dr Hui is the immediate past master of the Catholic Medical Guild