As you approach the end of your pregnancy, you're likely looking forward to going into labor both because you'll finally get to meet your baby and because delivery represents the end of the discomfort associated with late pregnancy. Though you might have heard they will induce labor, cinnamon and cloves don't appear to have any effect to this end.
Late Pregnancy
A "full term" pregnancy is one that has gone at least 37 weeks since the first day of your last menstrual period, or 35 weeks since conception, explain Heidi Murkoff and Sharon Mazel in their book "What To Expect When You're Expecting." A typical human pregnancy, however, lasts 40 weeks beyond the first day of your last menstrual period and some might go as long as 42 weeks. As such, there's a fairly long period during which you could potentially go into labor, which can understandably create some impatience.
Inducing Labor
If you're approaching or are at full term, you might be looking for something that will help start labor. Some midwives and practitioners of alternative or herbal medicine recommend certain preparations and teas to help "tone" the uterus, thin the cervix and move you toward delivery. Cinnamon and clove, however, are not among the teas or preparations that have been used traditionally and there's no scientific evidence to suggest that they will start labor.
Safety
Both cinnamon and clove are food spices and it's safe to consume them during pregnancy in food quantities. Clove, however, isn't safe during pregnancy in medicinal quantities, notes Medline Plus. There haven't been enough studies to demonstrate its safety during pregnancy when taken in large doses. Likewise, there haven't been enough studies to demonstrate the safety of cinnamon in large doses during pregnancy; AmericanPregnancy.org recommends it as a pleasant flavoring addition to herbal tea and food in small quantities.
Considerations
As much as you might be looking forward to the end of your pregnancy, there are good reasons to avoid inducing labor unless it's medically necessary, meaning that continuing the pregnancy would negatively impact either mother or baby's health. "The Wall Street Journal" notes that early delivery by even a few weeks can negatively impact the development of your baby's brain and that the healthiest way to approach the end of your pregnancy is to allow your labor to begin naturally, or at a time recommended by your doctor.