recurrence among women who bear children and no increase in birth defects among offspring has been observed.

While on tamoxifen, menstrual function may be disrupted and continuous tamoxifen use is believed to suppress ovulation in most women. Women can, however, become pregnant while taking tamoxifen, but its effect on fetal development is not known. It is therefore recommended that women who wish to become pregnant discontinue tamoxifen therapy several months before conceiving (Burstein and Winer, 2000). Because tamoxifen is recommended for 5 years, women with ER-positive tumors wanting to have children must consider delaying childbearing for more than 5 years.

Assisted reproductive techniques are an option to overcome fertility problems (Oktay, 2001; Oktay et al., 2003; Oktay and Sonmezer, 2004; Oktay et al., 2005; Partridge and Winer, 2005). The reproductive strategies typically require exposure to high levels of exogenous steroidal hormones, raising a concern regarding increased risk of recurrence or second cancer, especially for women with ER-positive tumors.19 Some promising approaches to preserve ovarian function have been suggested, but more research is needed (Friedlander and Thewes, 2003). The recent report of a live birth after the transplantation of cryopreserved ovarian tissue from a woman with Hodgkin’s lymphoma holds promise for younger women diagnosed with cancer (Donnez et al., 2004).

The extent and nature of breast-conserving surgery affect the likelihood of successful lactation in the affected breast. An estimated 25 to 30 percent of women are able to lactate after breast-conserving surgery and irradiation, but the majority of women continue to report difficult and inadequate lactation in the affected breast (Burstein and Winer, 2000).

Weight Gain20

At least half of women receiving adjuvant chemotherapy report gaining weight, with mean gains of 2.5 to 5 kg (5.5 to 11 pounds). More significant weight gain, as much as 10 to 20 kg (22 to 44 pounds), has been reported in as many as 20 percent of women. The exact cause of weight gain is uncertain, but it may be explained in part by decreased levels of physical


However, there is no evidence of an increased incidence of new cases of breast cancer among women undergoing in vitro fertilization, as compared with either the population at large or women with infertility who have not undergone in vitro fertilization. It is not known how reliably these findings apply to women who have already had breast cancer.


This section is based on the review of Partridge et al. (2001).

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