What Is Secondary Infertility?
Quick Answer
Secondary infertility is the inability to conceive or carry a pregnancy to term after previously giving birth without the help of fertility treatments. It is as common as primary infertility, affecting up to 11% of couples, and is caused by many of the same underlying factors, including age, ovulatory disorders, and male factor issues.
Markham Fertility Centre provides comprehensive evaluation and treatment for secondary infertility across five Ontario locations, with expertise in recurrent pregnancy loss and complex reproductive cases.
Secondary vs. Primary Infertility
| Primary infertility | Secondary infertility | |
| Definition | Unable to conceive after 12 months of trying (no prior births) | Unable to conceive or carry to term after at least one previous natural birth |
| Prevalence | Affects approximately 1 in 6 couples | Affects up to 11% of couples |
| Common causes | Same underlying factors | Same underlying factors, plus changes since the previous pregnancy |
| Treatment options | Identical | Identical |
| Emotional impact | Grief over not having a child | Added complexity of guilt, confusion, and social pressure from those who assume another pregnancy should happen easily |
The key distinction: secondary infertility is diagnosed only when the previous birth occurred without the use of fertility medications or treatments like IVF. If a prior pregnancy required fertility treatment, difficulty conceiving again is not classified as secondary infertility.
Common Causes
The causes of secondary infertility are largely the same as primary infertility. However, because time has passed since the first pregnancy, several factors may have changed.
Female factors:
- Age-related decline: Egg quality and quantity decrease over time. Fertility peaks around age 28 and declines sharply after 35. A gap of even 2 to 3 years between pregnancies can meaningfully reduce fertility.
- Ovulatory disorders: Conditions like PCOS can develop or worsen over time, disrupting regular ovulation
- Endometriosis: May progress between pregnancies and affect the ovaries, tubes, or uterine lining
- Uterine scarring: Scar tissue from a prior C-section, D&C, or other uterine surgery can interfere with implantation
- Uterine fibroids or polyps: Can develop after a first pregnancy and block or distort the uterine cavity
- Blocked fallopian tubes: Caused by pelvic infections, prior surgery, or endometriosis
- Weight changes: Significant weight gain or loss since the previous pregnancy can affect ovulation
- Lifestyle changes: Increased stress, smoking, or alcohol use since the first birth
Male factors:
- Declining sperm quality: Sperm count, motility, and morphology can decrease with age, illness, or lifestyle changes
- Varicocele: Enlarged veins in the testicle that affect sperm production, sometimes developing after a first child
- Hormonal changes: Late-onset hypogonadism or other endocrine conditions
- Medications or treatments: Certain drugs, cancer treatment, or surgeries affecting reproductive function
- Weight gain: The risk of infertility increases approximately 10% for every 20 additional pounds gained
Both partners:
- New partner: If you have a new partner, their fertility profile may introduce new challenges
- Unexplained infertility: In some cases, no identifiable cause is found despite thorough testing
When to See a Specialist
Because time and age are critical factors, the timeline for seeking help with secondary infertility is the same as for primary infertility:
| Your age | When to seek evaluation |
| Under 35 | After 12 months of trying without conception if you have regualr menstrual cycles |
| 35 to 39 | After 6 months of trying if you have regular menstrual cycles |
| 40 and older | As soon as you are ready to try for another child |
You should seek evaluation sooner if:
- You have a known condition like PCOS, endometriosis, or uterine scarring
- Your menstrual cycles have changed (shorter, irregular, or absent)
- You had a C-section or D&C that may have caused scarring
- You or your partner have experienced significant health or lifestyle changes since the previous pregnancy
- You struggled with primary infertility and now want to have another child
How Secondary Infertility Is Diagnosed
The diagnostic process mirrors a standard fertility workup, with additional attention to what may have changed since the last pregnancy:
- Medical history review: Pregnancy history, delivery method (vaginal vs. C-section), postpartum complications, menstrual cycle changes, and any new health conditions
- Hormone blood work: AMH, FSH, estradiol, TSH, and other markers to assess ovarian reserve and endocrine function
- Transvaginal ultrasound: Evaluates ovarian follicle count, uterine anatomy, fibroids, and polyps
- Hysterosalpingogram (HSG): Checks whether fallopian tubes are open
- Semen analysis: Assesses sperm count, motility, and morphology
In Ontario, initial consultations and most diagnostic testing are covered by OHIP.
Treatment Options
Treatment for secondary infertility is the same as for any form of infertility. The approach depends on the identified cause, your age, and your timeline:
- Lifestyle modifications: Weight management, quitting smoking, and reducing alcohol. May be sufficient when lifestyle factors are the primary contributor.
- Ovulation induction with timed intercourse: Oral medications (letrozole or Clomid) stimulate ovulation in patients with ovulatory disorders like PCOS
- IUI (intrauterine insemination): Washed sperm is placed directly in the uterus during ovulation. Effective for mild male factor, cervical issues, or unexplained infertility. Funded without limit through the Ontario Fertility Program.
- Surgery: Hysteroscopy can remove fibroids, polyps, or scar tissue. Laparoscopy can treat endometriosis or tubal issues.
- IVF (in vitro fertilization): Recommended when other treatments have failed, when fallopian tubes are blocked, when age is a pressing factor, or when genetic testing (PGT) is needed. One funded cycle per lifetime is available through the Ontario Fertility Program.
The Emotional Side of Secondary Infertility
Secondary infertility carries a unique emotional burden. Couples often feel:
- Confusion: “It worked before, why isn’t it working now?”
- Guilt: Feeling they should be grateful for the child they have
- Isolation: Others may minimize the struggle because the couple already has a child
- Pressure: Well-meaning questions from family about “when is the next one coming”
These feelings are valid. Fertility specialists and counsellors can provide support throughout the process. At Markham Fertility Centre, the care team recognizes that every patient’s story is different and that secondary infertility is just as deserving of attention and treatment as primary infertility.
Why Patients in Ontario Choose Markham Fertility Centre
- Expertise in complex cases, including recurrent pregnancy loss, recurrent implantation failure, and reproductive immunology
- Five reproductive endocrinologists providing continuity of care from consultation through the end of the first trimester
- Full treatment spectrum: Ovulation induction, IUI, IVF, surgery, PGT, and donor/surrogacy programs
- Ontario Fertility Program participant with funded IUI and IVF cycles available
- Five locations across Markham, Barrie-Innisfil, Oshawa, Orillia, and Sudbury
Book a consultation at Markham Fertility Centre →
FAQ
Is secondary infertility common?
Yes. It is approximately as common as primary infertility, affecting up to 11% of couples. About one-third of all infertility cases involve secondary infertility.
Can secondary infertility be treated successfully?
Yes. The treatments are the same as for primary infertility, and success rates are comparable. Up to 90% of infertility cases are treatable with medication, surgery, IUI, or IVF.
Does having a C-section cause secondary infertility?
A C-section alone does not cause infertility, but scar tissue from the procedure can sometimes affect the uterine cavity or interfere with implantation. A hysteroscopy can diagnose and treat uterine scarring if it is suspected.
Should I see a fertility specialist or my OB-GYN?
If you meet the age-based timelines above or have known risk factors, seeing a reproductive endocrinologist directly saves time. A fertility specialist can offer the full diagnostic workup and advanced treatments that a general OB-GYN cannot.