No-271-Delayed Child-Bearing



      To provide an overview of delayed child-bearing and to describe the implications for women and health care providers .


      Delayed child-bearing, which has increased greatly in recent decades, is associated with an increased risk of infertility, pregnancy complications, and adverse pregnancy outcome . This guideline provides information that will optimize the counselling and care of Canadian women with respect to their reproductive choices .


      Maternal age is the most important determinant of fertility, and obstetric and perinatal risks increase with maternal age .
      Many women are unaware of the success rates or limitations of assisted reproductive technology and of the increased medical risks of delayed child-bearing, including multiple births, preterm delivery, stillbirth, and Caesarean section . This guideline provides a framework to address these issues .


      Studies published between 2000 and August 2010 were retrieved through searches of PubMed and the Cochrane Library using appropriate key words (delayed child-bearing, deferred pregnancy, maternal age, assisted reproductive technology, infertility, and multiple births) and MeSH terms (maternal age, reproductive behaviour, fertility) . The Internet was also searched using similar key words, and national and international medical specialty societies were searched for clinical practice guidelines and position statements . Data were extracted based on the aims, sample, authors, year, and results .


      The quality of evidence was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care.


      The Society of Obstetricians and Gynaecologists of Canada.


      • 1.
        Women who delay child-bearing are at increased risk of infertility . Prospective parents, especially women, should know that their fecundity and fertility begin to decline significantly after 32 years of age . Prospective parents should know that assisted reproductive technologies cannot guarantee a live birth or completely compensate for age-related decline in fertility (II-2A).
      • 2.
        A fertility evaluation should be initiated after 6 months of unprotected intercourse without conception in women 35 to 37 years of age, and earlier in women > 37 years of age (II-2A).
      • 3.
        Prospective parents should be informed that semen quality and male fertility deteriorate with advancing age and that the risk of genetic disorders in offspring increases (II-2A).
      • 4.
        Women ≥ 35 years of age should be offered screening for fetal aneuploidy and undergo a detailed second trimester ultrasound examination to look for significant fetal birth defects (particularly cardiac defects) (II-1A).
      • 5.
        Delayed child-bearing is associated with increased obstetrical and perinatal complications . Care providers need to be aware of these complications and adjust obstetrical management protocols to ensure optimal maternal and perinatal outcomes (II-2A).
      • 6.
        All adults of reproductive age should be aware of the obstetrical and perinatal risks of advanced maternal age so they can make informed decisions about the timing of child-bearing (II-2A).
      • 7.
        Strategies to improve informed decision-making by prospective parents should be designed, implemented, and evaluated . These strategies should provide opportunity for adults to understand the potential medical, social, and economic consequences of child- bearing throughout the reproductive years (III-B).
      • 8.
        Barriers to healthy reproduction, including workplace policies, should be reviewed to optimize the likelihood of healthy pregnancies (III-C).

      Key Words


      ART (assisted reproductive technology), OR (odds ratio), ICSI (intracytoplasmic sperm injection), IUI (intrauterine insemination), LBW (low birth weight), PTD (preterm delivery), SGA (small for gestational age)
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