May 7, 2017
My patients often ask me why some couples seem to get pregnant immediately and others struggle for years to conceive, to which I respond that the timing can be different for everyone. The length of time it takes to conceive naturally varies from couple to couple, and therefore pinning down what's "normal" can be a bit of a challenge. While medical research studies vary widely on definitions of infertility, it has been demonstrated that the longer it takes the higher the chance that the couple is infertile.
As a general guide, most clinicians define infertility as no pregnancy after one year of trying. Couples generally get pregnant at the following rates, but bear in mind that age, reproductive health, and disease can impact these numbers.
38% were pregnant after 1 month
68% were pregnant after 3 months
81% were pregnant after 6 months
92% were pregnant after 12 months
Categories of Fertility Evaluation:
In general, patients are divided into four groups for consideration of fertility evaluation. A previous pregnancy doesn't change the groupings.
GROUP 1. Female age less than 35 with regular menstrual cycles. These patients usually have a good chance of conceiving. Therefore, they can continue trying for one year as 80-90% will likely conceive within a year.
GROUP 2. Female age greater than 35 with regular menstrual cycles. These patients have reduced fertility potential and a higher risk of complications including miscarriage and genetic anomalies. They need more aggressive or advanced therapy. These couples should seek assistance if they have tried for 6 months and have not been able to conceive.
GROUP 3. Female from all age groups with irregular cycles. Women with irregular or even no egg production have dramatically lower chances of conception. Patients with irregular cycles should seek assistance immediately, as the likelihood of spontaneous conception is low. Also, there are biological risks to having irregular cycles including increased risks of abnormal bleeding and endometrial cancer.
GROUP 4. Patients with a history of significant diseases or exposures that can impact fertility. These patients may include, but are not limited to:
These patients have a much higher prevalence of difficulty conceiving. They should seek help if they have not conceived within 6 months of trying.
Previous oral contraceptive use and infertility:
If you've recently come off of birth control, studies demonstrate that between 39-56% of patients will be able to conceive within 3 months of stopping any kind of hormonal birth control. The success rate increases to 94% within 12 months.
If you're thinking about your fertility and have questions, come see us:
We certainly do not turn away couples that are concerned and want earlier investigations. We also know the process can have significant psychological impact and distress. Please make an appointment if you're worried or unsure. We would be happy to help put you on the path to starting or growing your family.
Dr. Rahi Victory MD, FRCSC